∆=[tex](\frac{3}{5} )^2-4*\frac{1}{2} *(-\frac{18}{25} )=\frac{9}{25} +\frac{36}{25} =\frac{45}{25} =\frac{9}{5}[/tex]
p=[tex]\frac{-\frac{3}{5} }{2*\frac{1}{2} } =\frac{-\frac{3}{5} }{1} =-\frac{3}{5}[/tex]
q=[tex]\frac{-\frac{9}{5} }{4*\frac{1}{2} } =\frac{-\frac{9}{5} }{2} =\frac{-9}{5} *\frac{1}{2} =\frac{-9}{10}[/tex]
y=[tex]y=\frac{1}{2} (x+\frac{3}{5} )^2-\frac{9}{5}[/tex]